Clasp

ABSTRACT

An improved clasp includes first and second clasp portions, each having an attaching front edge, a mounting rear edge, a high-strength magnet imbedded adjacent the front edge and a receiving cavity adjacent the rear edge. The cavity receives an end of a band or strap. The first portion has a covering lip attached to an upper surface above the front edge. The lip extends outwardly toward the rear edge of the second portion upon joining of the portions. The lip extends between the side edges of the first portion. The improvement includes a protective ledge that extends outwardly from a lower surface of the second portion toward the rear edge of the first portion upon joining of the portions. The ledge extends between first and second side edges of the second portion. A bracelet that has the improved bracelet clasp prevents pinching of skin of the wearer&#39;s wrist upon joining.

FIELD OF INVENTION

This invention relates to the field of jewelry closures, and more specifically to a magnetic clasp that prevents pinching of the skin or fabric during fastening.

BACKGROUND OF THE INVENTION

Means for fastening one end of a clasp to another present unique challenges to the jewelry designer. The fastener or clasp must provide a secure attachment, to prevent loss of a valuable jewelry item. The clasp must also be attractive; adding to, rather than detracting from the esthetic effect of the jewelry design. If used for a bracelet, the wearer must be able to attach and remove the bracelet with only one hand. Further, it is desirable that the clasp does not pinch or otherwise injure the skin of the wearer or pinch fabric during attachment, wearing or removal.

The use of magnets in jewelry clasps offers the potential for easy attachment and removal with one hand, however, an additional problem is presented by their use. In order for the clasp to be sufficiently secure to prevent loss of the bracelet, the magnets employed must be reasonably strong. When two such magnets or a single magnet and a ferromagnetic substance are placed in close proximity, they tend to jump rapidly together. It is difficult to control this rapid movement with one hand and, as a result, the skin of the wearer's wrist is often pinched by the clasp as it is magnetically fastened. Many designs for magnetic jewelry clasps have been developed. Some relevant examples include the following.

U.S. Pat. No. 4,941,236, issued to Sherman et al., discloses a strap for holding a wristwatch has a pair of separable flexible strap ends adapted to curve around the wrist and to overlap one another to provide an overlapped section. At least one strap end of thermoplastic material has particles of permanently magnetizable material embedded in the thermoplastic material and magnetized to provide rows of alternating magnetic poles. The strap ends have surfaces contacting one another throughout the overlapped section and mutually nesting uniformly spaced interlocking teeth, whereby the magnetized particles provide a holding force resisting separation of the strap ends, while the nested teeth prevent sliding disengagement movement between strap ends.

U.S. Pat. No. 5,722,260, issued to Mangano is directed to a jewelry clasp comprising a pair of clam-shell-like clasp halves pivotally joined together and movable between an open and a closed position. A pair of hooks are mounted on the inner side of one of the clasp half for interchangeably and releasably attaching to the ends of a string of pearls or chain necklaces. A pair of magnets are attached to the inner side of the clasp halves to maintain the clasp halves in a normally closed position. The clasp arrangement is also useful for bracelets.

U.S. Pat. No. 5,099,659, issued to Carranza, et al. illustrates a magnetic clasp having first and second magnetized portions, each with a hole disposed in the center thereof. The two portions are magnetically attractive to each other but are divided with a gap at their interface to permit easy separation thereof. A third magnetic portion is sized to fit within the hole in the first and second rings. The magnetic prevents lateral movement of the two portions at their interface. The male portion has attached to its opposite ends a chain, each end of the chain being further attached to a stop sized larger than the hole in the rings.

U.S. Pat. No. 5,197,168, issued to Levy disclose a jewelry closure includes a pair of magnetic closure members for magnetically engaging together and a mechanical closure which acts as a second closure or safety feature. One or both closure members includes a magnet. The mechanical closure includes a substantially stiff wire member which pivots about a first member of the closure. An intermediate portion of the wire member is engaged adjacent an end face of the second member of the closure to prevent the magnetic members from being separated until after the wire member is pivoted to the open position. The mechanical closure must be released before the magnetic closure can be released. The jewelry closure includes an end ring on each member for attaching to jewelry. A spring ring closure may optionally be attached to each of these rings for attaching jewelry, such as a chain, to the magnetic closure. Using this feature, the magnetic closure may readily be used as a replacement clasp for jewelry.

U.S. Pat. No. 4,901,405, issued to Grover, et al. is directed to a cylindrical insert fitting easily through a retainer ring into a tubular chamber and held there by a magnetic structure. One end of a necklace is attached to a jewelry ring on the outside end of the insert and the other end is attached to a jewelry ring on the outside end of the tubular chamber. Materials in the chamber wall allow special magnetic structure in the tubular chamber to pull the insert aligned near the tubular chamber opening into the chamber and secures the cylinder end against the magnetic structure. The clasp holds together well yet is easily unfastened. Special fittings for locking the clasp parts together are not required.

U.S. Pat. No. 5,323,516, issued to Hartmann is directed to a closure, buckle, or clasp for connecting two free ends of a strap, a belt, a necklace, or a harness is disclosed that relies upon a mechanical keeper to at least aid in keeping the closure in an engaged condition, wherein the mechanical keeper is of magnetic material and is biased in a locked position by means of the force field of a magnet, thereby eliminating all springs or snug-fitting elements that could wear or lose their effectiveness over time. The magnetic keeper and the magnet may be parts of the same clasp element or they may be parts in separate clasp elements that are joined to effect closure of the clasp.

It is an objective of the present invention to provide a clasp or closure that can be an attractive part of a jewelry design while providing a strong and secure attachment. It is a further objective to provide such a fastener that is easily attached and detached with one hand. It is a still further objective of the invention to provide a clasp that is easily and economically manufactured. Finally, it is an objective of the present invention to provide a clasp that will not pinch the wrist of the wearer or adjacent fabric.

While some of the objectives of the present invention are disclosed in the prior art, none of the inventions found include all of the requirements identified.

SUMMARY OF THE INVENTION

The present invention addresses all of the deficiencies of prior art bracelet clasp inventions and satisfies all of the objectives described above.

(1) An improved clasp providing the desired features may be constructed from the following components. A clasp of the type includes first and second clasp portions. Each of the portions has an attaching front edge, a mounting rear edge, a high-strength magnet imbedded adjacent the front edge and a receiving cavity adjacent the rear edge. The cavity is sized and shaped to receive an end of a band or strap. The first clasp portion has a covering lip attached to an upper surface of the first portion above the front edge. The lip extends outwardly over the front edge toward the rear edge of the second clasp portion upon joining of the first and second portions. The lip extends from a first side edge to a second side edge of the first portion. The improvement includes a protective ledge. The ledge extends outwardly from a lower surface of the second clasp portion toward the rear edge of the first clasp portion upon joining of the first and second portions. The ledge extends from a first side edge to a second side edge of the second portion. The improved clasp is placed adjacent a wearer's skin, the first clasp portion is positioned adjacent the second clasp portion, magnetic force draws the portions together and the protective ledge prevents pinching of skin of the wearer.

(2) In a variant of the invention, at least one receiving notch is provided. The receiving notch is located adjacent the first side edge of the second clasp portion above the protective ledge. At least one mating tab is provided. The tab is located adjacent the first side edge of the first clasp portion below the covering lip. The mating tab is sized and shaped to fit slidably into the receiving notch. Fitting of the tab into the notch prevents lateral movement of the first clasp portion with respect to the second clasp portion in at least one direction upon joining of the first and second clasp portions.

(3) In another variant, the receiving notch is located adjacent the first and second side edges of the second clasp portion above the protective ledge. The mating tab is located adjacent the first and second side edges of the first clasp portion below the covering lip. Fitting of the tabs into the notches prevents lateral movement of the first clasp portion with respect to the second clasp portion in two directions upon joining of the first and second clasp portions.

(4) In still another variant, the at least one mating tab has an arcurate leading edge. The leading edge extends from an underside of the covering lip to a lower surface of the first clasp portion. The at least one receiving notch has a mating arcurate trailing edge. The trailing edge extends from a top surface of the protective ledge to an upper surface of the of the second clasp portion. The arcurate leading and trailing edges assist the wearer in fastening and unfastening the improved clasp.

(5) In yet another variant, the improved clasp further includes a flexible backing strap. The backing strap is formed of metallic mesh, leather, plastic or other similar materials. The strap has a first end, a second end, an upper surface and a lower surface. The ends are sized and shaped to fit slidably into the receiving cavities of the first and second clasp portions. The ends are attached to the receiving cavities.

(6) In a further variant, the flexible backing strap is attached to the receiving cavities using a method selected from a list consisting of adhesive fastening, welding, brazing, crimping, and wiring.

(7) In still a further variant, decorative material is adhered to the upper surface.

(8) In yet a further variant, the improved clasp further includes a flexible strap. The strap has a first end and a second end. The ends are sized and shaped to fit slidably into the receiving cavities of the first and second clasp portions. The strap is adhesively attached to the receiving cavities and is formed of material selected from the group consisting of leather, fabric, plastic, rubber and metal mesh.

(9) In another variant of the invention, the flexible strap is attached to the receiving cavities using a method selected from a list consisting of adhesive fastening, crimping, soldering and wiring.

(10) In still another variant, transverse gripping features are provided. The features are formed upon the upper surface and a lower surface of the first clasp portion and are formed upon the lower surface and an upper surface of the second clasp portion. The features provide assistance in opening and closing the improved clasp.

(11) In a final variant, the improved clasp further includes first and second relief cutouts. The cutouts penetrate lower walls of the receiving cavities of the first and second clasp portions, respectively.

An appreciation of the other aims and objectives of the present invention and an understanding of it may be achieved by referring to the accompanying drawings and the detailed description of a preferred embodiment.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the preferred embodiment of the invention illustrating the positioning of the clasp portions in closed position;

FIG. 2 is a perspective view of the FIG. 1 embodiment prior to closure;

FIG. 3 is a perspective view of a prior art clasp;

FIG. 4 is a perspective view of the first clasp element of the FIG. 1 embodiment illustrating the high strength magnet and covering lip;

FIG. 5 is a perspective view of the second clasp element of the FIG. 1 embodiment illustrating the high strength magnet and protective ledge;

FIG. 6 is a cross-sectional view of the FIG. 1 embodiment illustrating the first and second clasp portions separated;

FIG. 7 is a cross-sectional view of the FIG. 1 embodiment illustrating the first and second clasp portions joined;

FIG. 8 is a perspective view of FIG. 1 embodiment illustrating a metallic mesh flexible backing strap;

FIG. 9 is a perspective view of FIG. 1 embodiment illustrating a metallic mesh flexible backing strap with decorative materials attached; and

FIG. 10 is a perspective view of FIG. 1 embodiment illustrating a flexible strap.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(1) FIGS. 1, 2 and 4-10 illustrate an improved clasp 10 providing the desired features that may be constructed from the following components. As illustrated in prior art FIG. 3, a clasp 14 of the type includes first 18 and second 22 clasp portions. Each of the portions 18, 22 has an attaching front edge 26, a mounting rear edge 30, a high-strength magnet 34 imbedded adjacent the front edge 26 and a receiving cavity 38 adjacent the rear edge 30. The cavity 38 is sized and shaped to receive an end 42 of a band or strap 46. The first clasp portion 18 has a covering lip 50 attached to an upper surface 54 of the first portion 18 above the front edge 26. The lip 50 extends outwardly over the front edge 26 toward the rear edge 30 of the second clasp portion 22 upon joining of the first 18 and second 22 portions. The lip 50 extends from a first side edge 52 to a second side edge 56 of the first portion 18. The improvement, as illustrated in FIGS. 1, 2 and 4-10, includes a protective ledge 58. The ledge 58 extends outwardly from a lower surface 62 of the second clasp portion 22 toward the rear edge 30 of the first clasp portion 18 upon joining of the first 18 and second 22 portions. The ledge 58 extends from a first side edge 66 to a second side edge 70 of the second portion 22. A bracelet 74 that has the improved clasp 10 is placed about a wrist of a wearer (not shown), the first clasp portion 18 is positioned adjacent the second clasp portion 22, magnetic force draws the portions 18, 22 together and the protective ledge 58 prevents pinching of skin (not shown) of the wearer's wrist or adjacent fabric (not shown).

(2) In a variant of the invention, as illustrated in FIGS. 4 and 5, at least one receiving notch 78 is provided. The receiving notch 78 is located adjacent the first side edge 66 of the second clasp portion 22 above the protective ledge 58. At least one mating tab 82 is provided. The tab 82 is located adjacent the first side edge 52 of the first clasp portion 18 below the covering lip 50. The mating tab 82 is sized and shaped to fit slidably into the receiving notch 78. Fitting of the tab 82 into the notch 78 prevents lateral movement of the first clasp portion 18 with respect to the second clasp portion 22 in at least one direction 86 upon joining of the first 18 and second 22 clasp portions.

(3) In another variant, the receiving notch 78 is located adjacent the first 66 and second 70 side edges of the second clasp portion 22 above the protective ledge 58. The mating tab 82 is located adjacent the first 52 and second 56 side edges of the first clasp portion 18 below the covering lip 50. Fitting of the tabs 82 into the notches 78 prevents lateral movement of the first clasp portion 18 with respect to the second clasp portion 22 in two directions 86, 90 upon joining of the first 18 and second 22 clasp portions.

(4) In still another variant, the at least one mating tab 82 has an arcurate leading edge 94. The leading edge 94 extends from an underside 98 of the covering lip 50 to a lower surface 102 of the first clasp portion 18. The at least one receiving notch 78 has a mating arcurate trailing edge 106. The trailing edge 106 extends from a top surface 110 of the protective ledge 58 to an upper surface 114 of the of the second clasp portion 22. The arcurate leading 94 and trailing 106 edges assist the wearer in fastening and unfastening the improved clasp 10.

(5) In yet another variant, as illustrated in FIGS. 8 and 9, the improved clasp 10 further includes a flexible backing strap 118. The backing strap 118 is formed of metallic mesh 122, leather (not shown), plastic (not shown) or other materials (not shown). The strap 118 has a first end 126, a second end 130, an upper surface 134 and a lower surface 136. The ends 130, 134 are sized and shaped to fit slidably into the receiving cavities 38 of the first 18 and second 22 clasp portions. The ends 126, 130 are attached to the receiving cavities 38.

(6) In a further variant, the flexible backing strap 118 is attached to the receiving cavities 38 using a method selected from a list consisting of adhesive fastening, welding, brazing, crimping, soldering and wiring.

(7) In still a further variant, as illustrated in FIG. 9, decorative material 138 is adhered to the upper surface 134.

(8) In yet a further variant, as illustrated in FIG. 10, the improved clasp 10 further includes a flexible strap 142. The strap 142 has a first end 146 and a second end 150. The ends 142, 146 are sized and shaped to fit slidably into the receiving cavities 38 of the first 18 and second 22 clasp portions. The strap 142 is adhesively attached to the receiving cavities 38 and is formed of material selected from the group consisting of leather, fabric, plastic, rubber, metallic mesh or other materials.

(9) In another variant of the invention, the flexible strap 142 is attached to the receiving cavities 38 using a method selected from a list consisting of adhesive fastening, crimping, soldering and wiring.

(10) In still another variant, as illustrated in FIG. 10, transverse gripping features 154 are provided. The features 154 are formed upon the upper surface 54 and a lower surface 158 of the first clasp portion 18 and are formed upon the lower surface 62 and an upper surface 162 of the second clasp portion 22. The features 154 provide assistance in opening and closing the improved clasp 10.

(11) In a final variant, as illustrated in FIGS. 1 and 2, the improved clasp 10 further includes first (not shown) and second 170 relief cutouts. The cutouts 170 penetrate lower walls 174, 178 of the receiving cavities 38 of the first 18 and second 22 clasp portions, respectively.

The improved clasp 10 has been described with reference to particular embodiments. Other modifications and enhancements can be made without departing from the spirit and scope of the claims that follow. The improved clasp can be used with shoes, purses and various clothing applications. 

1. An improved clasp, of the type comprising first and second clasp portions, each of said portions having an attaching front edge, a mounting rear edge, a high-strength magnet imbedded adjacent said front edge and a receiving cavity adjacent said rear edge, said cavity being sized and shaped to receive an end of a band, said first clasp portion having a covering lip attached to an upper surface of said first portion above said front edge, said lip extending outwardly over said front edge toward said rear edge of said second clasp portion upon joining of said first and second portions, said lip extending from a first side edge to a second side edge of said first portion, the improvement comprising: a protective ledge, said ledge extending outwardly from a lower surface of said second clasp portion toward said rear edge of said first clasp portion upon joining of said first and second portions; said ledge extending from a first side edge to a second side edge of said second portion; and wherein said improved clasp is placed adjacent a wearer's skin, said first clasp portion is positioned adjacent said second clasp portion, magnetic force draws said portions together and said protective ledge prevents pinching of skin of said wearer.
 2. The improved clasp, as described in claim 1, further comprising: at least one receiving notch, said receiving notch disposed adjacent said first side edge of said second clasp portion above said protective ledge; at least one mating tab, said tab disposed adjacent said first side edge of said first clasp portion below said covering lip, said mating tab being sized and shaped to fit slidably into said receiving notch; and wherein fitting of said tab into said notch prevents lateral movement of said first clasp portion with respect to said second clasp portion in at least one direction upon joining of said first and second clasp portions.
 3. The improved clasp, as described in claim 2, wherein: said receiving notch is disposed adjacent said first and second side edges of said second clasp portion above said protective ledge; said mating tab, is disposed adjacent said first and second side edges of said first clasp portion below said covering lip; and wherein fitting of said tabs into said notches prevents lateral movement of said first clasp portion with respect to said second clasp portion in two directions upon joining of said first and second clasp portions.
 4. The improved clasp, as described in claim 2, wherein: said at least one mating tab has an arcurate leading edge, said leading edge extending from an underside of said covering lip to a lower surface of said first clasp portion; said at least one receiving notch has a mating arcurate trailing edge, said trailing edge extending from an top surface of said protective ledge to an upper surface of said of said second clasp portion; and wherein said arcurate leading and trailing edges assist said wearer in fastening and unfastening said improved clasp.
 5. The improved clasp, as described in claim 1, further comprising a flexible backing strap, having a first end, a second end, an upper surface and a lower surface, said ends being sized and shaped to fit slidably into said receiving cavities of said first and second clasp portions, said ends being attached to said receiving cavities, said backing strap being formed of material selected from the group consisting of: metallic mesh, leather, plastic and fabric.
 6. The improved clasp, as described in claim 5, wherein said flexible backing strap is attached to said receiving cavities using a method selected from a list consisting of: adhesive fastening, welding, brazing, crimping, soldering and wiring.
 7. The improved clasp, as described in claim 5, wherein decorative material is adhered so said upper surface.
 8. The improved clasp, as described in claim 1, further comprising a flexible strap, said strap having a first end, a second end, said ends being sized and shaped to fit slidably into said receiving cavities of said first and second clasp portions, being adhesively attached to said receiving cavities and being formed of material selected from the group consisting of: leather, fabric, plastic, rubber and metal mesh.
 9. The improved clasp, as described in claim 8, wherein said flexible backing strap is attached to said receiving cavities using a method selected from a list consisting of: adhesive fastening, crimping, soldering and wiring.
 10. The improved clasp, as described in claim 1, further comprising: transverse gripping features, said features being formed upon said upper surface and a lower surface of said first clasp portion and being formed upon said lower surface and an upper surface of said second clasp portion; and said features providing assistance in opening and closing said improved clasp.
 11. The improved clasp, as described in claim 1, further comprising first and second relief cutouts, said cutouts penetrating lower walls of said receiving cavities of said first and second clasp portions. 